Filtering product data in sidebar

Hi,

I'm developing a clothing store and want to be able to filter the data (in a sidebar) by category, brand, styles etc. I see other (mainly php) sites doing this by appending to the url eg &brand=adidas&category=shorts etc. but not sure if this is the way to go or if rails provides a better way.

What is an effective way of doing this in Rails? Some tips and links would be appreciated.

Thanks,